1. Field of the Invention
The present invention relates to a method and apparatus for downloading a program in a digital signal processor (DSP), more particularly, a DSP having a dual CPU employing hand shaking.
2. Discussion of Related Art
At present, the number of handheld phone users is rapidly soaring and new products for various communicating systems and services are being introduced worldwide. New products includes Code Division Multiplex Access 2000 (CDMA 2000) and Wide-CDMA (W-CDMA) as third-generation communications. In Europe, GSM/GPRS products as the 2.5th generations have been developed successively. The third-generation communicating system requires high speed transmission, multimedia service and compatibility with other communication systems. As an example, a wireless terminal is supported by a dual mode, and related software requires several kinds of protocol stacks.
In these communication systems, a digital signal processor (DSP) is utilized to decentralize a load of a micro control unit (MCU). The DSP is a chip capable of performing a boot-loading and requires a driving program to perform actual operation. Such a driving program can be downloaded from a program stored at a memory connected to the micro control unit (MCU), and storing it at an internal program memory.
A problem in such a conventional system is that much time is needed to download the stored program because the DSP has to be reset, and then the desired program is downloaded, and after the downloading is completed, the DSP needs to be reset again to execute the downloaded program.